Lecture Notes: Calculating Mean, Median, Mode, and Range

Introduction

This lecture provides a quick guide on how to calculate the mean, median, mode, and range using examples from two questions.

Question 1: James and the Spinner

• Scenario: James spins a spinner labeled 1 to 5, ten times.
• Data Collected: Results of the spins (not explicitly listed, but inferred from the calculations).

Calculating the Mode

• Definition: Mode is the number that appears the most frequently in a data set.
• Calculation:
  • Observe the numbers: Number 4 appears most frequently.
  • Mode: 4

Calculating the Mean

• Definition: Mean is the average of all numbers.
• Calculation Steps:
  1. Sum all the numbers: Total = 28
  2. Count the numbers (given as 10 spins).
  3. Divide the total by the count: 28 / 10 = 2.8
  • Mean: 2.8

Calculating the Range

• Definition: Range is the difference between the highest and lowest numbers in a data set.
• Calculation:
  • Highest number = 5
  • Lowest number = 1
  • Subtract the lowest from the highest: 5 - 1 = 4
  • Range: 4

Question 2: Simone's Mobile Phone Usage

• Scenario: Simone records the number of minutes spent on her mobile phone over a week (7 days).

Calculating the Median

• Definition: Median is the middle number in an ordered data set.
• Data Collected: 5, 6, 8, 10, 13, 90, 24
• Calculation Steps:
  1. Order the numbers from smallest to largest: 5, 6, 8, 10, 13, 24, 90
  2. Identify the middle number in the sequence.
  • In an ordered list of 7 numbers, the median is the 4th number.
  • Median: 10

Summary

• Mode focuses on frequency.
• Mean involves summation and division for averaging.
• Range considers the spread between extremes.
• Median requires ordering data to find the center point.

These calculations provide fundamental statistical measures to understand data sets.